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31.
Michael Zeutzius Toshiaki Setoguchi Toshihiro Nakano Hideo Miyanishi Kunio Terao Saga University Honjo Saga - Japan 《热科学学报(英文版)》2000,(2)
~nonEmphasising time characterishcs and contIDI, onlyfew workll'v is av'ailable among the numerous reports onPulse combustors. Rare work deals with tWin Pulsecombustorsls] or combined pulse combustor-"dinesystemsl']. Kenffield15] obtained with a combinedconvenhonal Pulse combustor-tulbine system acombushon Pressals gain of 3-7% and a totalPerformance Of the combustor-"dine system for Pulsecombushon 40% higher than that of steady'combushonwhat aught also be due tO the brine characteristics.… 相似文献
32.
An artificial olfactory, which is called an electronic nose system (e-nose), is studied for realizing new human–machine interface. The system consists of sensor unit and a signal processing unit. There are some types of sensors for the sensor unit, metal oxide semiconductor gas sensors (MOGS) and quartz crystal microbalance gas sensors are useful in our study. Our system in this paper has MOGS. Many of MOGS utilize an effect of an oxidation–reduction reaction on the surface of the sensors. One of the features of the sensor, the character of the sensor is changed by temperature of the sensors. In this paper, we build a extend output sensor unit using this feature, and show experimental result of classification applying multilayer perceptron. In the experiment, we choose soy sauce as classification targets because we are considering applying the system for management of cooked foods. 相似文献
33.
Junko Matsuki Tomoko Sasaki Koichi Yoza Junichi Sugiyama Hideo Maeda Ken Tokuyasu 《Journal of Applied Glycoscience》2019,66(4):113
Rice-gel prepared by the following three steps: rice grain cooking, shearing of the cooked rice, and cooling for gel formation, is expected as a novel food ingredient for modification of various food products such as bread and noodles. To meet the demand for high-throughput systems for research and developments on the new rice gels, herein we established a mini-cooking system for preparation of rice gel samples from grains using a small-scale viscosity analyzer (Rapid Visco Analyzer; RVA). Polished rice grains (4 g) were cooked with 22 mL of water in a canister, and the paddle equipped in the canister was rotated at 2,000 rpm for 30 min (80 °C was used as a representative) to shear the cooked rice. The sheared paste was cooled to 10 °C at 160 rpm, and the initial gelation property was evaluated by viscosity analysis within the RVA. Alternatively, the sheared paste was transferred to an acrylic mold and kept at 4 °C for 0, 1, 3, and 5 days for determination of the hardness with a compression test. Compressive forces required to penetrate 20 % thickness for three tested rice cultivars were measured, and the trend of the value shifts during preservation is similar to the corresponding trend obtained in 300-g grain scale laboratory tests, whereas the individual values were halved in the former. This small cooking method could offer a useful assay system for a rapid evaluation in the breeding programs and in the high-throughput screening of additives for the modification of properties. 相似文献
34.
Yoshitomo Isomae Takahiro Ishinabe Yosei Shibata Hideo Fujikake 《Journal of the Society for Information Display》2019,27(4):251-258
We achieved uniform liquid crystal (LC) alignment in lattice‐shaped dielectric walls 1 μm in pitch; this is a prerequisite when driving the individual pixels of spatial light modulators, facilitating the development of practical electronic holographic displays with a wide field of view. In lattice‐shaped dielectric walls, LC alignment becomes unstable, particularly on the bottom and the walls; the LC directors tend to align parallel to the walls. To overcome this problem, we created lattice‐shaped walls featuring partition plates that allow uniform LC alignment. When the plates confine LCs to small regions exhibiting spatial anisotropy, the LC elastic effect and wall anchoring forces align the LC directors parallel to the long anisotropic axis. We found that pixels 0.5 μm × 1.0 μm in pitch formed if the partition plates were sufficiently thick to allow shielding of electric field leakage. 相似文献
35.
Kuwae S Ohda T Tamashima H Miki H Kobayashi K 《Journal of Bioscience and Bioengineering》2005,100(5):502-510
Antithrombin is a serine protease inhibitor that inactivates several coagulation proteases, primarily thrombin and factor Xa. The Chinese hamster ovary (CHO) cell line transfected with a vector expressing recombinant human antithrombin (rAT) and a selectable marker, glutamine synthetase (GS), was cultivated in a 2-l fed-batch culture process using serum-free, glutamine-free medium. To maximize the rAT yield, effects of culture pH, balanced amino acid feeding, and an increased glutamate concentration on cell metabolism and rAT production were investigated. When cells were grown at pH values of 6.6, 6.8, 7.0, and 7.2, the maximum cell density and maximum lactate concentration decreased with decreasing pH. The highest production level of rAT was obtained at culture pH 6.8 due to the extended culture lifetime. Compared to the imbalanced amino acid feeding at culture pH 6.8, the balanced amino acid feeding increased the amount of rAT activity by 30% as a result of an increased viable cell number. A decrease in the specific glucose consumption rate (q(Glc)) with increasing culture time was observed in all the above-mentioned experiments, while the glucose concentration was maintained above 0.7 g l(-1). In addition, a decrease in the specific rAT production rate (q(rAT)) was observed after the depletion of lactate in the late cultivation stage. Taken together, these results suggest that the reduced availability of cellular energy caused by the decrease in q(Glc) and depletion of lactate led to the decrease in q(rAT). This decrease in q(rAT) was partially prevented by increasing the residual glutamate concentration from 1 mM to 7 mM, thus resulting in an additional 30% increase in the amount of rAT activity. The optimized fed-batch culture process yielded 1.0 g l(-1) rAT at 287 h of cultivation. 相似文献
36.
The effect of NH4F addition on the high-anodic behaviors of various DSA-type electrodes was investigated in a mixture of sulfuric acid and ammonium sulfate. The pronounced effect of NH4 addition was observed on DSA-type Ti/RuO2, Ti/IrO2?TiO2 electrodes, but not observed on the other electrodes studied. The close relationship was found between the increment of the electrode potential caused by the NH4 addition and the quantity of F? adsorbed on the electrode surface. The effect of NH4F addition was considered to be resulted from the adsorption of F? on the electrode surface, and the presence of adsorbed F? was directly proved. 相似文献
37.
Hayashi A Aoyagi H Yoshimura T Tanaka H 《Journal of Bioscience and Bioengineering》2007,103(4):358-367
It is becoming increasingly difficult to isolate novel useful microorganisms from the natural environment using conventional screening methods based on pure culture techniques. A novel method for screening microorganisms in symbiotic association with insects was developed. This method involves the following two steps. In the first step, the existence of desired microorganisms that grow well by degrading difficult-to-degrade materials in the gut of insects is detected using the survivability of insects as an indicator. In the second step, the desired microorganisms are selected from the surviving insects. The second step is based on an idea that the guts of insects act as continuous-culture systems whereby microorganisms that cannot degrade diet components are washed out whereas those that can degrade diet components are retained and made to multiply in the gut. Coptotermes formosanus Shiraki was fed with an artificial diet containing phenol as a model of lignin-derived and difficult-to-degrade compound. Each C. formosanus feeding on an artificial diet containing 100 mg/l phenol had different levels of adaptation to the toxicity of phenol. About 20% of C. formosanus fed with an artificial diet containing 100 mg/l phenol died within a few days whereas others survived for more than 10 d. The structure of the intestinal microorganisms of the surviving C. formosanus fed with the 100 mg/l phenol artificial diet gradually changed and was very different from that of the bacterial communities obtained from the enrichment culture of wood-feeding C. formosanus using an artificial medium containing phenol as a sole carbon source. Furthermore, Only three species (as DGGE band) were detected from the gut of wood-feeding C. formosanus, whereas 200 times more phenol-degrading microorganisms were detected in the gut of C. formosanus feeding on a phenol artificial diet. Out of these nine species (as DGGE band) of phenol-degrading microorganisms were isolated. The screening method developed in this study can also be applied to various insects, leading to the isolation of various microorganisms that can degrade difficult-to-degrade compounds. 相似文献
38.
The heterogeneous phase transition of the organic vapours, cyclohexane and p-xylene, on a cold substrate was observed by cooling the substrate at a slow rate under reduced pressure conditions. Either organic vapour at a vapour pressure lower than 130 Pa formed directly solid crystals but p-xylene vapour at a higher vapour pressure formed liquid condensates with subsequent formation of solid crystals. The dependence of the critical supersaturation ratios on the critical temperatures and the physical properties of the organic vapours has been clarified by the equation derived on the basis of classical nucleation theory. 相似文献
39.
Akihiko Kono Katsuya Shimizu Hajime Nakano Yousuke Goto Yusuke Kobayashi Toshiaki Ougizawa Hideo Horibe 《Polymer》2012,53(8):1760-1764
This paper discusses the positive-temperature-coefficient effects of resistivity in Ni particle-dispersed poly(vinylidene fluoride) (PVDF) composites based on experiment results from SEM, DSC, and pressure-volume-temperature (PVT) measurements. The melting points of composites with Ni content of 20, 30, 40, and 50vol.% were equal to that of pure PVDF. The PTC effects in composites with Ni content of 40 and 50vol.% occurred at temperatures near the melting point of the PVDF matrix, whereas those in composites with Ni content of 20 and 30vol.% occurred at temperatures below the melting point of the PVDF matrix. We found that the PTC effect occurs even without melting of the matrix polymer. Moreover, we determined that a slight increase in specific volume at temperatures below the melting point of the matrix polymer acts fully as a driving force for forming a gap between fillers. This suggestion was backed up by theoretical analyses using percolation theory and a thermal-fluctuation-induced tunneling model. 相似文献
40.
Koji Sugano Yuki Uchida Osamu Ichihashi Hideo Yamada Toshiyuki Tsuchiya Osamu Tabata 《Microfluidics and nanofluidics》2010,9(6):1165-1174
Gold nanoparticles with diameters of a few tens of nanometer and a narrow size distribution were synthesized using a pulsed mixing method with a microfluidic system which consists of a Y-shaped mixing microchannel and two piezoelectric valveless micropumps. This mixing method enables control of the mixing speed of gold salts and reducing agent by changing the switching frequency of the micropumps, which was our focus to improve the particle size distribution, which is an essential parameter in gold nanoparticle synthesis. In the proposed method, the mixing time was inversely proportional to the switching frequency and the minimum mixing time was 95 ms at a switching frequency of 200 Hz. During synthesis experiments, the mean diameter of the synthesized gold nanoparticles was found to increase, and the coefficient of variation of particle size was found to decrease with decreasing mixing time. We successfully improved the coefficient of variation to less than 10% for a mean diameter of around 40 nm. 相似文献